Download sources by default

Fixes #117

Author: mickaelistria

org.eclipse.m2e.core/src/org/eclipse/m2e/core/internal/preferences/MavenPreferenceInitializer.java

@@ -36,7 +36,7 @@ public void initializeDefaultPreferences() {
     store.putBoolean(MavenPreferenceConstants.P_OFFLINE, false);
     store.put(MavenPreferenceConstants.P_GLOBAL_UPDATE_POLICY, MavenPreferenceConstants.GLOBAL_UPDATE_POLICY_DEFAULT);
 
-    store.putBoolean(MavenPreferenceConstants.P_DOWNLOAD_SOURCES, false);
+    store.putBoolean(MavenPreferenceConstants.P_DOWNLOAD_SOURCES, true);
     store.putBoolean(MavenPreferenceConstants.P_DOWNLOAD_JAVADOC, false);
 
     store.put(MavenPreferenceConstants.P_OUTPUT_FOLDER, "target-eclipse"); //$NON-NLS-1$